I think skinnies will be in for a very long time, and if that doesn't look good on certain people, many will look towards the straight leg trend because it is even and doesn't make people look awkwardly proportioned. There will always be skinny people in the world and the skinny jean will always flatter their body types.
As far as bootcut and flares go, I think flares aren't so much out as people are just not wearing them as much. that sounds weird, I know. I think it's just that the most current sillouette is skinny jean obsessed. They do come out and play sometimes, like when people are just hanging out and don't care too much about being "fashionable." However, a lot of celebrities are still wearing bootcut and flares because well, theyre young and grew up with the bootcut trend and it's kind of hard to part with sucha classic shape.
This is a long post, whoops. Really, you're going to Europe, which means people buy clothing that fits them really well and wear them to death before purchasing something "trendy." If youa re traveling, bring whatever you are comfortable in. A good pair of bootcut jeans looks 100x better than a sloppy skinny that doesn't flatter your body.